Composition for external use and method for stabilizing the same

Abstract

To obtain a composition for external use excellent in high-temperature stability and to provide a method for stabilizing the same.SOLUTION: The external composition comprises hypromellose and a dihydric alcohol.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a topical composition and a method for stabilizing the same. [Background technology]

[0002] For example, Patent Document 1 discloses a composition for external use that contains a cellulose derivative including hypromellose and a polyhydric alcohol and forms a foam upon use. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 130035 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, if a topical composition is placed in a car or near a window, the temperature may rise and become too high. If the topical composition has poor high-temperature stability and aggregates such as gels are formed, clogging may occur, especially when the composition is filled in a pump container. Patent Document 1 does not take into consideration the high-temperature stability of the topical composition. Therefore, an object of the present invention is to provide a topical composition having excellent high-temperature stability and a method for stabilizing the same. [Means for solving the problem]

[0005] A topical composition according to one embodiment of the present invention contains hypromellose and a dihydric alcohol.

[0006] According to the above configuration, the high temperature stability of the topical composition can be improved. [Effects of the Invention]

[0007] The topical composition of the present invention can improve high-temperature stability, and in particular can suppress the formation of aggregates even at temperatures of 50°C or higher. DETAILED DESCRIPTION OF THE INVENTION

[0008] The topical composition of the present invention contains hypromellose and a dihydric alcohol.

[0009] Hypromellose is a hydroxypropyl methylcellulose in which some of the hydroxyl groups of cellulose have been replaced with methoxy or hydroxypropoxy groups. Hypromellose acts, for example, as a thickening component to adjust the viscosity of the topical composition or as a foaming component to form foam when the topical composition is used.

[0010] Hypromellose is available with different degrees of substitution of the methoxy group or hydroxypropoxy group, and examples of Japanese Pharmacopoeia hypromellose include hypromellose of substitution type 2910, which has a degree of substitution of 28.0 to 30.0% for the methoxy group and 7.0 to 12.0% for the hydroxypropoxy group, hypromellose of substitution type 2906, which has a degree of substitution of 27.0 to 30.0% for the methoxy group and 4.0 to 7.5% for the hydroxypropoxy group, and hypromellose of substitution type 2208, which has a degree of substitution of 22.0 to 24.0% for the methoxy group and 8.5 to 10.5% for the hydroxypropoxy group. In the topical composition of the present invention, hypromellose of substitution type 2906 and hypromellose of substitution type 2208 are preferred in terms of improving high-temperature stability, with hypromellose of substitution type 2208 being particularly preferred.

[0011] The lower limit of the amount of hypromellose in the topical composition is preferably 0.02 wt% or more, more preferably 0.1 wt% or more. This allows the topical composition to be filled into a foaming container and discharged into a suitable foam state. On the other hand, the upper limit of the amount of hypromellose is preferably 0.8 wt% or less, more preferably 0.4 wt% or less. This allows the feel (especially the slimy feel) of the topical composition during use to be improved.

[0012] Examples of the dihydric alcohol include propylene glycol, dipropylene glycol, 1,3-butylene glycol, ethylene glycol, and pentylene glycol. To improve the high-temperature stability of the topical composition of the present invention, propylene glycol, dipropylene glycol, 1,3-butylene glycol, and pentylene glycol are preferred, with propylene glycol, dipropylene glycol, and 1,3-butylene glycol being particularly preferred. The dihydric alcohols may be used alone or in combination.

[0013] Furthermore, the lower limit of the amount of dihydric alcohol in the topical composition is preferably 3 wt% or more, more preferably 9 wt% or more, in order to improve high-temperature stability, while the upper limit of the amount of dihydric alcohol is not particularly limited, but is preferably 50 wt% or less.

[0014] The topical composition preferably contains water. The amount of water in the topical composition is preferably 90 wt% or less. In particular, when hypromellose with a degree of substitution of 2208 is used, high-temperature stability can be improved.

[0015] Furthermore, as described above, by including hypromellose and a dihydric alcohol in the topical composition, the topical composition can be stabilized at high temperatures. In other words, this can be said to be a method for stabilizing a topical composition by allowing a dihydric alcohol to coexist with hypromellose.

[0016] In the above-mentioned topical composition, the aggregates that form when the composition is heated to high temperatures are thought to be derived from hypromellose. In other words, the above-mentioned topical composition can be said to be a topical composition that suppresses the formation of aggregates due to hypromellose by containing a dihydric alcohol.

[0017] The topical composition may contain other ingredients selected appropriately within the scope of the present invention, as long as the effects of the present invention are not impaired. Examples of such ingredients include medicinal ingredients, surfactants (nonionic surfactants, cationic surfactants, anionic surfactants, etc.), diluents, solubilizers, pH adjusters, viscosity adjusters, stabilizers, preservatives, fragrances, colorants, etc.

[0018] The above-mentioned external composition is preferably used as a medicine or cosmetic by blending it with active pharmaceutical ingredients or ingredients effective as cosmetics.

[0019] The medicinal ingredient is not particularly limited, but may be, for example, a heparinoid. The amount of the heparinoid in the topical composition is preferably 0.01 to 5 wt%, more preferably 0.1 to 0.3 wt%.

[0020] The pH of the topical composition is preferably 5.5 to 7.0. By adjusting the pH within this range, the stability of the topical composition over time can be improved and skin irritation during use can be reduced. The pH can be appropriately adjusted using a pH adjuster. Examples of pH adjusters for adjusting the pH of the topical composition to the above range include potassium dihydrogen phosphate, citric acid, sodium hydroxide, potassium hydroxide, sodium lactate, sodium citrate, L-arginine, and diisopropanolamine.

[0021] The topical composition can be used by applying it directly to the skin, but is preferably used in the form of a foam. Therefore, the topical composition is preferably filled into a former container that can be foamed when dispensed. Examples of former containers include pump formers and squeeze formers that are filled with the topical composition as is, and aerosol containers that are filled with the topical composition together with a propellant. The topical composition of the present invention has improved high-temperature stability and inhibits the formation of gel-like aggregates, so even when filled into a former container and used, clogging can be inhibited and the composition can be used in the form of a foam. [Example]

[0022] The present invention will be specifically explained below with reference to examples, but these examples are not intended to limit the scope of the present invention.

[0023] Compositions for external use were prepared by mixing the components in the amounts shown in Tables 1 to 3.

[0024] [Table 1]

[0025] [Table 2]

[0026] [Table 3]

[0027] The pH of the topical compositions prepared in the Examples and Comparative Examples was measured, and the appearance and foaming properties were evaluated as described below. The results are shown in Tables 1 to 3.

[0028] (Appearance evaluation) The appearance of the topical compositions was visually observed immediately after preparation and after storage overnight at 5°C, 40°C, 50°C, and 60°C. The appearance was judged as follows: ○: No gelled or other aggregates were observed. ×: The occurrence of aggregates such as gelled matter was observed.

[0029] (Evaluation of foaming properties) The prepared topical compositions were filled into pump former containers, and the presence or absence of foaming properties when discharged was evaluated. The foaming properties were evaluated as follows. ○: Foaming property was exhibited ×: No foaming properties were observed [Industrial Applicability]

[0030] According to the present invention, a topical composition having excellent high-temperature stability can be provided.

Claims

1. A topical composition comprising hypromellose and a dihydric alcohol.

2. The topical composition according to claim 1, wherein the dihydric alcohol comprises at least one selected from dipropylene glycol, propylene glycol, 1,3-butylene glycol, and pentylene glycol.

3. The topical composition according to claim 1 or 2, wherein the amount of the dihydric alcohol is 3.0 wt% or more.

4. The composition for external use according to claim 1 or 2, wherein the amount of hypromellose blended is 0.02 to 0.8 wt %.

5. The topical composition according to claim 1 or 2, wherein the hypromellose has a degree of substitution of methoxy groups of 22.0 to 24.0% and a degree of substitution of hydroxypropoxy groups of 8.5 to 10.5%.

6. The topical composition according to claim 1 or 2, further comprising a heparinoid.

7. The topical composition according to claim 1 or 2, which forms a foam upon use.

8. The topical composition according to claim 7, which is filled in a former container.

9. A method for stabilizing a composition for external use, characterized by causing hypromellose to coexist with a dihydric alcohol.

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